It is well known in the prior art to provide a gas cap and housing assembly. The gas cap and housing assembly is connected to a fuel filler neck assembly which in turn is attached to a fuel tank. A gas cap may be removed from the assembly and gasoline may be inserted into the fuel filler neck assembly by a gasoline pump nozzle for transfer into the fuel tank. The gas cap and housing assembly provides structure to which the fuel filler neck assembly is attached. The fuel filler neck assembly typically includes at least one fill hose and at least one vent hose which are relatively long flexible pieces made entirely of rubber through which the gas is transferred from the housing assembly to the fuel tank. Preferably, the fill and vent hoses are flexible for permitting curved routing paths between the housing assembly and the fuel tank.
It is also known in the prior art to have vehicles, especially trucks, which are modified or upfitted for different vehicle applications to a predetermined range of final vehicle wheelbases (lengths) and widths. These modifications are often performed after initial assembly of the vehicle frame with the fuel tank and fuel filler neck assembly and the final dimensions may not be known at the time of initial assembly. To accommodate these various vehicle dimensions, it is known in the prior art to provide extra long lengths of fill hose and vent hose or extra pieces of fill and vent hose during initial assembly which will accommodate the longest and widest possible vehicle dimensions.
However, this has the disadvantage of having to measure and cut the fill and vent hoses to a particular size at the time of the upfitting while discarding the remainder of the fill and vent hoses which are unused. Alternately, the extra fill and vent hoses will need to either be connected to the base hoses or will be discarded if not needed. The fill and vent hoses are typically fairly expensive rubber hoses and large portions of these are discarded by the upfitters when the vehicles are not completed with the maximum set of predetermined vehicle dimensions. In addition, any elastomeric hoses will have a certain degree of hydrocarbon permeability. It is desirable to minimize the length of elastomeric hoses in the fuel filler neck assembly to reduce evaporative emissions as much as possible.